Internet (1969)

1963, the Advanced Research Project Agency unit, set up by the U.S. Defense Department,

began to build a computer network. Driven by fear of the Soviet nuclear threat, it aimed to link computers

at different locations, so researchers could share data electronically without
having fixed routes

between them, making the system less vulnerable to attacks even nuclear ones.

Data was converted into telephone signals 

using a modem (modulator-demodulator), developed at AT&T In the late 1950's. In the 1960's, key advances were made including "packet switching" the system

of packaging, labeling, and routing data that enables it to be delivered across the network

between machines. Paul Baran (b. 1926) proposed this system, which broke each message

down into tiny chunks. These would be fired into the network, which would then route ("switch")

the various pieces to the desired destination

So, if chunks of a message were traveling from Seattle to New York via Dallas, but Dallas

suddenly went offline, the network would automatically route via Denver Instead. Different parts-

or "packets"-of a message would go by different routes, before being reassembled back into the

original message at their destination, even if they arrived in the wrong order.

Baran published his concept in 1964, and five years later the new network-called ARPANET--Went live
As the threat of nuclear war receded in the early 1970s, ARPANET was renamed the

Internet and effectively opened to all users. Since then, the development of e-mail, the creation

of the World Wide Web, and browser technology has enabled the Internet to become a rich communication facility. SC